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Bulletin of Volcanology

, Volume 72, Issue 6, pp 677–692 | Cite as

The Holocene Pucón eruption of Volcán Villarrica, Chile: deposit architecture and eruption chronology

  • C. Silva ParejasEmail author
  • T. H. Druitt
  • C. Robin
  • H. Moreno
  • J.-A. Naranjo
Research Article

Abstract

The Pucón eruption was the largest Holocene explosive outburst of Volcán Villarrica, Chile. It discharged >1.0 km3 of basaltic-andesite magma and >0.8 km3 of pre-existing rock, forming a thin scoria-fall deposit overlain by voluminous ignimbrite intercalated with pyroclastic surge beds. The deposits are up to 70 m thick and are preserved up to 21 km from the present-day summit, post-eruptive lahar deposits extending farther. Two ignimbrite units are distinguished: a lower one (P1) in which all accidental lithic clasts are of volcanic origin and an upper unit (P2) in which basement granitoids also occur, both as free clasts and as xenoliths in scoria. P2 accounts for ∼80% of the erupted products. Following the initial scoria fallout phase, P1 pyroclastic flows swept down the northern and western flanks of the volcano, magma fragmentation during this phase being confined to within the volcanic edifice. Following a pause of at least a couple of days sufficient for wood devolatilization, eruption recommenced, the fragmentation level dropped to within the granitoid basement, and the pyroclastic flows of P2 were erupted. The first P2 flow had a highly turbulent front, laid down ignimbrite with large-scale cross-stratification and regressive bedforms, and sheared the ground; flow then waned and became confined to the southeastern flank. Following emplacement of pyroclastic surge deposits all across the volcano, the eruption terminated with pyroclastic flows down the northern flank. Multiple lahars were generated prior to the onset of a new eruptive cycle. Charcoal samples yield a probable eruption age of 3,510 ± 60 14C years BP.

Keywords

Villarrica Volcano Pucón eruption Pyroclastic flow Ignimbrite Radiocarbon age 

Notes

Acknowledgements

We thank Jorge Clavero, Silke Lohmar, and Alain Gourgaud for discussions and Wes Hildreth and Jocelyn McPhie for their reviews. Silke Lohmar and Laurence Girolami helped in the field. The project was financed by the ECOS/CONICYT Project No. C01U03 and by the French Institute de Recherche pour le Développement (IRD).

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • C. Silva Parejas
    • 1
    • 2
    • 5
    Email author
  • T. H. Druitt
    • 1
  • C. Robin
    • 1
  • H. Moreno
    • 3
  • J.-A. Naranjo
    • 4
  1. 1.Laboratoire Magmas et VolcansUniversité Blaise Pascal, CNRS & IRDClermont-FerrandFrance
  2. 2.Departamento de GeologíaUniversidad de ChileSantiagoChile
  3. 3.OVDASServicio Nacional de Geología y MineríaTemucoChile
  4. 4.Servicio Nacional de Geología y MineríaProvidenciaChile
  5. 5.Programa de Riesgo VolcánicoServicio Nacional de Geología y MineríaSantiagoChile

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